Prefer use of resourceUuid index over resourceType when selecting from resourceentity table

[LZRS]

IMPORTANT: All PRs must be linked to an issue (except for extremely trivial and straightforward changes).

Fixes #[issue number]

Description
For queries that select from the resourceentity table and have filters to resourceentity.resourceUuid, prefer to use resourceentity.resourceUuid` over resourceentity.resourceType . Both are indexed but the ``resourceentity.resourceUuid is unique and is faster

Alternative(s) considered
Have you considered any alternatives? And if so, why have you chosen the approach in this PR?

Type
Choose one: (Bug fix | Feature | Documentation | Testing | Code health | Builds | Releases | Other)

Screenshots (if applicable)

Checklist

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[jingtang10]

can you pls add some stats from testing.

@aditya-07 please can you add comments.

[LZRS]

Given

fhirEngine.search<Task> {
    filter(Task.IDENTIFIER, { value = of("routine_screening") })
    filter(Task.STATUS, { value = of("ready") })
}

Previously this would generate the query

SELECT a.resourceUuid, a.serializedResource
FROM ResourceEntity a
WHERE a.resourceType = 'Task'
  AND a.resourceUuid IN (SELECT resourceUuid
                         FROM TokenIndexEntity
                         WHERE resourceType = 'Task'
                           AND index_name = 'identifier'
                           AND index_value = 'routine_screening')
  AND a.resourceUuid IN (SELECT resourceUuid
                         FROM TokenIndexEntity
                         WHERE resourceType = 'Task'
                           AND index_name = 'status'
                           AND index_value = 'ready')

with the query plan

QUERY PLAN
|--SEARCH a USING INDEX index_ResourceEntity_resourceType_resourceId (resourceType=?)
|--LIST SUBQUERY 1
|  `--SEARCH TokenIndexEntity USING COVERING INDEX index_TokenIndexEntity_index_value_resourceType_index_name_resourceUuid (index_value=? AND resourceType=? AND index_name=?)
`--LIST SUBQUERY 2
   `--SEARCH TokenIndexEntity USING COVERING INDEX index_TokenIndexEntity_index_value_resourceType_index_name_resourceUuid (index_value=? AND resourceType=? AND index_name=?)

Testing on db with 125206 resources, and 109654 Tasks, the query takes around

Run Time: real 2.247 user 0.104013 sys 0.346853

The changes in this PR, would be generating the query

SELECT a.resourceUuid, a.serializedResource
FROM ResourceEntity a
WHERE a.resourceUuid IN (SELECT resourceUuid
                         FROM TokenIndexEntity
                         WHERE resourceType = 'Task'
                           AND index_name = 'identifier'
                           AND index_value = 'routine_screening')
  AND a.resourceUuid IN (SELECT resourceUuid
                         FROM TokenIndexEntity
                         WHERE resourceType = 'Task'
                           AND index_name = 'status'
                           AND index_value = 'ready');

resulting in the query plan

QUERY PLAN
|--SEARCH a USING INDEX index_ResourceEntity_resourceUuid (resourceUuid=?)
|--LIST SUBQUERY 1
|  `--SEARCH TokenIndexEntity USING COVERING INDEX index_TokenIndexEntity_resourceType_index_name_index_value_resourceUuid (resourceType=? AND index_name=? AND index_value=?)
`--LIST SUBQUERY 2
   `--SEARCH TokenIndexEntity USING COVERING INDEX index_TokenIndexEntity_resourceType_index_name_index_value_resourceUuid (resourceType=? AND index_name=? AND index_value=?)

Testing on db with 125206 resources, and 109654 Tasks, the query takes around

Run Time: real 0.003 user 0.000442 sys 0.000643

Also Note: the db returned 0 rows since it didn't have any Task with identifier routine_screening

[LZRS]

For a database with 166293 resources and 137517 Encounters,

The query

SELECT a.resourceUuid, a.serializedResource
FROM ResourceEntity a
WHERE a.resourceType = 'Encounter'
  AND a.resourceUuid IN (SELECT resourceUuid
                         FROM TokenIndexEntity
                         WHERE resourceType = 'Encounter'
                           AND index_name = '_id'
                           AND ((index_value = 'cf5f865f-602b-4c8c-9ece-acd4761f6eca' OR
                                 index_value = '16fa13cb-a977-44ab-9db5-ccc62a38a414') OR
                                (index_value = 'b228ff4d-ee37-4752-ba96-1d198adb9951' OR
                                 index_value = '89138401-c9b5-4b57-9871-edac67a6fbde')));

takes

Run Time: real 3.826 user 0.163887 sys 0.493112

while the query with preference to the resourceUuid index

SELECT a.resourceUuid, a.serializedResource
FROM ResourceEntity a
WHERE a.resourceUuid IN (SELECT resourceUuid
                         FROM TokenIndexEntity
                         WHERE resourceType = 'Encounter'
                           AND index_name = '_id'
                           AND ((index_value = 'cf5f865f-602b-4c8c-9ece-acd4761f6eca' OR
                                 index_value = '16fa13cb-a977-44ab-9db5-ccc62a38a414') OR
                                (index_value = 'b228ff4d-ee37-4752-ba96-1d198adb9951' OR
                                 index_value = '89138401-c9b5-4b57-9871-edac67a6fbde')));

takes

Run Time: real 0.004 user 0.000646 sys 0.000949